The present invention is related to a steel cable lock structure with internal multidirectional locking effect, which can be easily operated to control the winding and unwinding of the steel cable in multiple directions.
FIG. 7 shows a conventional steel cable releasing/retracting controlling structure of a steel cable lock (Taiwanese Patent Publication No. 131371). The lock includes a housing 50, a steel cable retracting/releasing device 51, multiple numeral wheels 52, a press button lock bolt 53, a resilient abutting pin 54 and steel cable clutch controller 55. The rear end of the steel cable retracting/releasing device 51 is equipped with an engaging head 511 which can be inserted and locked in a latch hole 501. When the engaging head 511 is inserted and locked, the abutting pin 54 is pressed to move toward the press button 551 in the housing 50. The steel cable clutch controller 55 is disposed on the lower press button 551 which is pivotally disposed on a shaft 552 at the button hole. The press button 551 has a button bar 553 extending to inner side of the housing 50. The innermost end is connected with a dog 554 for engaging with the ratchets of the reel. A stop board 556 is connected with upper side of the press button 551. In locked state, the stop board 556 is stopped by lower end of the pressed abutting pin 54, whereby the press button 551 cannot be pressed. The button bar 553 via a button spring 558 is resiliently connected with a cable pressing plate 557 to push the dog 554 in normal state to engage with the ratchets 555 of the reel. When the dog 554 is engaged with the ratchets 555, the cable pressing plate 557 presses the steel cable 512 to prevent the steel cable 512 from being drawn. When the lower press button 551 is released, the cable pressing plate 557 synchronously presses the steel cable 512 to further prevent the steel cable 512 from rushing back into the housing 50 due to inertia when the cable winding device 51 is instantaneously stopped by the dog 554. This avoids loosening of the wound cable and truly controls the extensible length of the steel cable 512. However, there are still some shortcomings existing in the operation of the dog 554 as follows:
1. The center of the pivot shaft 552 of the dog 554 is positioned behind the dog 554. Accordingly, when the dog 554 is engaged with the ratchets 555 of the reel, the length from the center of the pivot shaft 552 to the tip of the dog 554 is longer than the length from the center of the pivot shaft 552 to the tip of the ratchets 555. This causes that when the dog 554 is turned to disengage from the ratchets 555, it is necessary to first apply a force to push and reversely turn the reel. In addition, the application force arm is shorter than the resistance force arm. Therefore, it is necessary to apply a greater force for pressing the press button to disengage the dog 554 from the ratchets 555. Under such circumstance, the reel can be rotated to release the steel cable 512.
2. It can be found from FIG. 7 that the steel cable 512 is pulled in such a direction that a push force is exerted onto the cable pressing plate 557 and the button bar 553 to loosen the same. This makes it impossible to truly restrict the steel cable 512 and the reel. In addition, due to the pulling force exerted onto the cable pressing plate 557 by the steel cable 512, a very great torque is created at the pivot shaft 552 of the steel cable clutch controller 55. This is very likely to lead to damage of the stop board 556.
3. Moreover, the inner end of the resilient abutting pin 54 must bear greater lateral pressing force coming from the button bar 553 when locked. Such lateral pressing force exerted onto the end section is not an optimal force application measure with respect to the resilient abutting pin 54. (The optimal measure should be an action force in axial direction of the abutting pin.) This tends to bias the resilient abutting pin 54 to abrade the wall of the pin hole through which the abutting pin 54 is passed.
4. When locked, the inner end of the resilient abutting pin 54 extends into the swinging space of the stop board 556 to stop the stop board 556 so as to prevent the press button 551 from being pressed. However, it is found that the length from the center of the pivot shaft 552 to the stop board 556 is much shorter than the length from the center of the pivot shaft 552 to the rear end of the dog 554 or the button bar 553. Therefore, in locked state, in the case that a small gap exists between the stop board 556 and the resilient abutting pin 54, the rear end of the dog 554 or the button bar 553 may have larger swinging tolerance. This seriously affects the reliability of controlling of the steel cable retracting/releasing device 51 and cable pressing plate 557 by the steel cable clutch controller 55.
It is therefore a primary object of the present invention to provide a steel cable lock structure with internal multidirectional locking effect. In the steel cable lock structure, a dog is resiliently deflectable to engage with the ratchets of the reel. When a lower end press button is pressed, an oblique slot of the lower end press button biases and guides the dog. Basically, simply by means of slightly pushing the lower end press button toward the dog, the oblique slot can drive and deflect the dog in conformity with the rotational direction of the reel releasing the steel cable so as to disengage the dog from the ratchets. Therefore, when releasing the steel cable, the pressing force applied to the lower end press button is apparently minified so that the operation is facilitated.
It is a further object of the present invention to provide the above steel cable lock structure in which a stop plate is disposed at rear end of the dog. When the lower end press button is released, the stop plate instantaneously abuts against the steel cable to stop the steel cable from rushing back. In unlocked state, in the case that the lower end press button is not pressed, the steel cable still cannot be drawn out. This is because when the dog is resiliently deflected to constantly engage with the ratchets of the reel, the stop plate also constantly abuts against the steel cable. Moreover, the steel cable is drawn out in such a direction that the dog is more tightly engaged with the ratchets so that the steel cable can be hardly drawn out.
It is still a further object of the present invention to provide the above steel cable lock structure in which the lower end press button, button bar and dog are driven in the same straight line. This obviates the shortcoming of poor reliability of the conventional leverage swinging type.
It is still a further object of the present invention to provide the above steel cable lock structure in which the locking device is formed with numeral windows corresponding to the respective numeral wheels. A window shielding plate is drivingly connected with the upper end press button for pressing the locking device. In unlocked state, when pressing the upper end press button, the correct numbers of the numeral wheels in the windows are shielded by the window shielding plate. Therefore, when unlocked, an unauthorized person can hardly see the numbers.
The present invention can be best understood through the following description and accompanying drawings wherein: